It's actually getting wild "out there". WordPress was once a really good choice for a blogging platform. Now, majority of the "popular" plugins are strictly businesses. E.g. You can use our API for 100 calls a month, either pay up to use this plugin more or wait another 30 days to get another 100 calls.

And yes, it is mostly the cost of convenience. For example, I manage my own server not because it's cheaper (which it is), but because I don't need to pay extra $50 a month to get a "managed" experience.

Same goes for very mundane tasks like image compression. You can pay some company to do it on your behalf, or you can go to GitHub and grab a fully functional library to compress 1,000 photos in an instant.